The research tests a cognitive-perceptual interpretation of how visceral-autonomic behavior becomes conditioned. A central proposition is that evoked brain potentials may be used as indices of information processing and cognitive activity during autonomic learning. The central procedure involves the concurrent measurement of evoked cortical potentials and electrodermal responses in experimental arrangements of human classical conditioning. Major classes of research proposed are (1) observations of early components of evoked potentials during autonomic conditioning with short interstimulus intervals; (2) observations of later components (e.g., CNVs) when longer interstimulus intervals are used, and relating those components to anticipatory electrodermal responses and to responses following the second, or signaled, stimulus; and (3) the use of verbal recognition test measures as a second index of cognitive activity in situations involving semantic conditioning of both categories of behavior: evoked brain potentials and electrodermal changes.